This is a multicenter randomized study of multiple dose, exogenous surfactant in full term infants with moderate ventilatory failure who have adverse progression of disease. Infants will be randomized to control and surfactant groups only if they are stable. All treatment after randomization will be administered by individuals blind to assignment. The primary outcome variable will be adverse progression of disease defined by blood gas measures and increased use of ventilary support. The sample size needed to detect a 40% reduction in adverse progression is 206. Support from the GCRC is being sought only for data management.